Containers, and more specifically metallic beverage containers, generally have a neck on an upper portion of a container body that is adapted for interconnection to an end closure. The end closure is typically formed from a flat sheet of metallic material and generally includes a pull tab or other form of stay on tab (“SOT”). Beverage containers commonly store carbonated beverages, thus, both the container body and the end closure are required to withhold internal pressures up to 90 psi without catastrophic failure or permanent deformation. Further, the end closure must be manufactured, stacked, shipped, and sent to a filler prior to being seamed onto a container body filled with a carbonated beverage. Therefore, the container body and end closure must be designed to resist deformation and failure while utilizing thin metallic materials and allowing compact stacking during shipping and manufacturing.
Food and beverage containers with pull tabs or SOTs are generally known. Various SOTs and related features are disclosed, by way of example, in U.S. Pat. No. 7,926,675 to Rieck et al., the entire disclosure of which is hereby incorporated by reference in its entirety. Known devices typically contain a score and an anti-fracture score that defines a tear panel. A user may pivot the pull tab into the tear panel to dispense the contents of the container. Such an arrangement, particularly where can contents are placed under pressure, pose various complications and challenges with opening the container. Such complications include, but are not limited to, rapid score flexure or breakage, which may result in the tear panel disconnecting from the end closure and shooting outward from the end closure and thus becoming a “missile.”
Previous attempts have been made to manufacture end closures with controlled opening characteristics. One such feature is a check slot, which is generally a portion of the score that is cut shallower than the rest of the score, or in other words, the check slot has a larger residual of material underneath the score. A check slot is disclosed in U.S. Patent Publication No. 2011/0303672 to Fields at al., the entire disclosure of which is hereby incorporated by reference in its entirety. The additional material underneath the check slot inhibits propagation of the fracture that occurs when a user pivots a pull tab into the tear panel. However, more score residual can make the end closure difficult to open, and a score with a non-uniform depth adds complexity to the manufacturing process of the end closure, and thus expense.
Other attempts to provide an end closure with a tear panel that will not detach and turn into a missile include an end closure with one anti-missile feature that is an indention or depression crossing the anti-fracture score but not crossing the main score and a check slot portion of the main score. However, each of these features require different tooling and machinery, and thus, manufacturing can be expensive.
Due to the numerous limitations associated with the prior art described above, the following disclosure describes an improved end closure that is adapted for interconnection to a container body and that employs anti-missile features, which eliminate the missiling effect of the tear panel without increasing the difficulty of opening the container.